JPH11241659A - Fuel supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a piping and reduce costs by incorporating a check valve and a pressure regulator for returning excess fuel into a fuel tank by opening a valve when fuel liquid pressure in a supply passage for leading fuel liquid filtered by a filter element into an engine is a prescribed pressure value or more, integratedly with each other in the supply passage. SOLUTION: When a vehicular switch key is turned on and a fuel tank 4 in a fuel tank 1 is driven, fuel sucked through a filter 6 is boosted up, and is filtered while the fuel is supplied from an inlet 10b of a fuel filter 10 to an outlet 10c bypassing a filter element 8. Filtered fuel is passed a supply passage 12, and is supplied to an engine bypassing a check valve 13. When fuel liquid pressure in the supply passage 12 is increased for prescribed pressure or more, a valve for a pressure regulator 9 which is arranged integratedly with an upper housing 11 together with the check valve 13 is opened in a communicating passage 15 divided from the supply passage 12, excess fuel is delivered into a fuel tank 1, and fuel pressure is held within a constant range.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel supply device in which a fuel pump and a fuel filter installed in a fuel tank of a vehicle or the like are integrated.

[0002]

2. Description of the Related Art FIG.
FIG. 6 is a side sectional view showing a conventional fuel supply device in which a fuel pump and a fuel filter disclosed in Japanese Patent Publication No.
Is a schematic diagram of a fuel supply system, and FIG.
FIG. 1 is a cross-sectional view of a conventional fuel pump disclosed in Japanese Patent Publication No. 94-94. In the figure, reference numeral 1 denotes a fuel tank, which has an opening on the upper surface. Reference numeral 2 denotes a bracket which is oil-tightly attached to an opening on the upper surface of the fuel tank 1, reference numeral 3 denotes a column extending from the bracket 2 toward the bottom of the fuel tank 1, and reference numeral 4 denotes a column 3.
, A check valve provided at a discharge port 4 a of the fuel pump 4, and 6 a fuel pump 4
Is a filter attached to the suction port 4b. Reference numeral 7 denotes a fuel filter, which is oil-tightly mounted on the bracket 2 and has a supply port 7a to the engine outside the fuel tank 1, and a suction port 7b of the fuel filter 7 is connected to a discharge port 4a of the fuel pump 4. . The housing 7c of the fuel filter 7 is formed of a resin molded product, and has a filter element 8 disposed therein. Reference numeral 9 denotes a pressure regulator, which opens a valve when the fuel supply pressure to the engine through a communication passage 7d exceeds a predetermined value, returns excess fuel to the fuel tank 1, and keeps the fuel supply pressure within a certain range.

Next, the operation of the conventional vehicle fuel supply device will be described. When the switch key of the vehicle is turned on to start the engine, the fuel pump 4 is driven and the fuel liquid is discharged.
Check valve 6 by pressurizing to 0 to 300 KPa (kilopascal)
Is fed into the fuel filter 7 from the suction port 7b via Filter element 8 in fuel filter 7
The fuel liquid from which dust and foreign matter in the fuel liquid have been filtered is supplied to the engine from the supply port 7a. The fuel pressure supplied to the engine by the pressure regulator 9 connected through the communication passage 7c downstream of the filter element 8 in the fuel filter 7 is maintained within a certain range. When the fuel pump 4 is stopped by turning off the switch key, the check valve 5 prevents the fuel liquid from the fuel filter 7 from flowing back to the fuel pump 4, and the inside of the fuel filter 7 and the supply port 7a.
To maintain the fuel pressure.

[0004]

In the conventional fuel supply apparatus as described above, the check valve 5 is provided upstream of the fuel filter 7, so that even when the engine is stopped by turning off the switch key of the vehicle. The high pressure state of the fuel liquid in the fuel filter 7 is maintained, and the fuel
Of the high-pressure fuel liquid is constantly applied to the housing 7c. For this reason, it is necessary to select the shape of the housing 7c and the resin material that can withstand the useful life of the vehicle in a state where stress is constantly applied, which is expensive.

The present invention has been made to solve the above-mentioned problems, and the time for supplying fuel for driving the engine (running of the vehicle) is a fraction of the service life of the vehicle. Focusing on a certain point, an object is to provide an inexpensive fuel supply device by simplifying the selection of the shape and resin material of the housing 7c by limiting the application of the stress of the high-pressure fuel liquid to the housing 7c when the engine is driven. And

[0006]

According to a first aspect of the present invention, there is provided a fuel supply system for a vehicle, comprising a molded article of a polymer material having a built-in filter element for filtering a fuel liquid supplied under pressure from a fuel pump. A check valve provided in a supply path for guiding the fuel liquid filtered by the filter element to the engine to prevent backflow of the fuel liquid from the engine;
When the fuel pressure in the supply path is equal to or higher than a predetermined pressure, a pressure regulator that opens a valve to return excess fuel liquid into the fuel tank and adjust the fuel pressure in the supply path is integrally incorporated.

According to a second aspect of the present invention, there is provided a fuel supply device for a vehicle, wherein a check valve is provided at a nipple at the end of a supply path downstream of a branch point to a pressure regulator.

According to a third aspect of the present invention, there is provided a fuel supply device for a vehicle, wherein a check valve is provided between a fuel filter and a branch point to a pressure regulator.

According to a fourth aspect of the present invention, there is provided a fuel supply device for a vehicle, wherein a housing of the fuel filter is constituted by an upper housing which forms the fuel filter in an oil-tight manner by joining with a main housing enclosing the filter element. The fuel pump holding section is integrally formed, and a pressure regulator is connected and attached to a supply path provided in the upper housing.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a side sectional view of a fuel supply device according to a first embodiment of the present invention, and FIG. 2 is a schematic diagram of a fuel supply system according to the first embodiment. In the figure, 1, 4, 8, and 9 are the same as those in the description of the conventional device. Reference numeral 10 denotes a fuel filter, in which a filter element 8 is disposed in a main housing 10a made of a resin molded product of a polymer material.
b and an outlet 10c. Further, a pump holding portion 10d is provided at a portion where the main housing 10a extends downward. Reference numeral 11 denotes an upper housing made of a resin molded product of the fuel filter 10. After the filter element 8 is inserted into the main housing 10a, the upper housing 1
1 and a required portion of the contact portion 11a of the main housing 10a are oil-tightly closed by heat welding or the like so that the flow of the fuel liquid in the fuel filter 10 is formed from the inlet 10b, the filter element 8, and the outlet 10c. At the same time, an outer edge of the upper housing 11 is integrally formed with a bracket flange 11b for attaching the fuel supply device to the fuel tank 1.

Reference numeral 12 denotes a supply passage which communicates with an outlet 10c of the fuel filter 10 and supplies fuel to the engine. This supply path 12 is also integrally formed with the upper housing 11. Reference numeral 13 denotes a check valve, which is provided in the nipple portion 14 at the end of the supply path 12 and prevents a backflow of the fuel liquid from the engine to the fuel filter 10. The supply passage 12 and the outlet 10c are simultaneously welded and connected to the opening of the main housing 10a when the upper housing 11 is closed with oil by heat welding. Reference numeral 15 denotes a communication path branched from the supply path 12, and a pressure regulator 9 is attached to a tip of the communication path.
Excess fuel liquid from the pressure regulator 9 is returned to the fuel tank. A communication pipe 16 connects the fuel pump 4 and the inlet 10b of the fuel filter 10.

In the fuel supply device configured as described above,
When the fuel pump 4 is driven by turning on the switch key of the vehicle, the fuel liquid pressurized to 200 to 300 KPa (kilopascal) is sent from the inlet 10b of the fuel filter 10 to the outlet 10c via the filter element 8. . During this time, the filter element 8 filters dust and foreign matter in the fuel liquid. The filtered fuel liquid is supplied to the engine through a supply path 12 and a check valve 13. The pressure regulator 9 attached to the communication passage 15 branched from the supply passage 12 to maintain the fuel hydraulic pressure in the engine within a certain range is supplied with an excessive pressure from the fuel pump 4 and when the pressure rises due to a decrease in the fuel consumption of the engine. Is the supply channel 1
The excess fuel liquid is discharged from the fuel tank 2 into the fuel tank 1. When the fuel pump 4 is stopped by turning off the switch key, the check valve 13
Holds the fuel pressure of the engine. However, when the pressurized fuel liquid passes through the fuel pump 4 when the fuel pump 4 stops, the pressure inside the fuel filter 10 is reduced to normal pressure, and the main housing 10a is released from the stress caused by the pressurized fuel liquid when the vehicle is not operating. .

Accordingly, the stress of the high-pressure fuel liquid on the main housing 10a can be eliminated outside the engine driving time. The running time (engine driving time) is a fraction of the durable period of the vehicle, and the durable period of the main housing 10a can be extended as compared with the case where the stress of the high-pressure fuel liquid is constantly applied. In particular, in the resin molding shape in which the pump holding portion 10d is formed integrally with the main housing 10a as described above, the flow of the resin at the time of molding becomes complicated, and in a shape in which the strength is partially insufficient in the main housing 10a. In addition, the shape of the main housing 10a and the selection of the resin material are facilitated, and an inexpensive fuel supply device can be provided. Further, the check valve 13 is easily attached to the nipple portion 14 at the end of the supply path 12. Then, the excess fuel liquid due to the pressure adjustment of the supply path 12 is directly returned to the fuel tank 1 from the pressure regulator 9 connected and integrated with the supply path 12, so that the return pipe is not required, and the apparatus is not required. Can be simplified.

Embodiment 2 FIG. FIG. 3 is a side sectional view of a fuel supply device according to a second embodiment of the present invention, and FIG. 4 is a schematic diagram of a fuel supply system according to the second embodiment. In the figure, 1,
Reference numerals 4, 8, 9 to 16 are the same as those described in the first embodiment. The fuel supply device of the second embodiment has a check valve 13
Is provided between the outlet 10c of the fuel filter 10 in the supply path 12 and the branch of the communication path 15 of the pressure regulator 9, and the valve body of the check valve 13 is vertically arranged.

By providing the check valve 13 at this position, the pressure regulator 9 can always release the excess fuel hydraulic pressure on the engine side. In addition, the engine and the supply path 1
The operation instability of the check valve 13 due to the influence of the pipe connection with the valve 2 can be eliminated.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a fuel supply device according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram of a fuel supply system according to Embodiment 1 of the present invention.

FIG. 3 is a side sectional view of a fuel supply device according to a second embodiment of the present invention.

FIG. 4 is a schematic diagram of a fuel supply system according to Embodiment 2 of the present invention.

FIG. 5 is a side sectional view of a conventional fuel supply device.

FIG. 6 is a schematic diagram of a fuel supply system of a conventional fuel supply device.

FIG. 7 is a sectional view of a conventional fuel pump.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Fuel tank, 4 Fuel pump, 8 Filter element 9 Pressure regulator, 10 Fuel filter 10a Main housing, 10d Pump holding part 11 Upper housing, 12 Supply path, 13 Check valve 14 Nipple part

Claims (4)

[Claims] 1. A fuel supply device immersed in a fuel tank, wherein a polymer pump includes a fuel pump for pressurizing and supplying a fuel liquid and a filter element of a fuel filter for filtering the fuel liquid from the fuel pump. And a supply path for guiding the supply fuel liquid filtered from the fuel filter to the engine. When the fuel pressure in the supply path is equal to or higher than a predetermined pressure, the valve is opened to release the excess fuel liquid. A pressure regulator that adjusts the fuel pressure in the supply path and a check valve that prevents backflow of the fuel liquid from the engine in the supply path, and is integrated with the fuel. Feeding device. 2. The fuel supply device according to claim 1, wherein the check valve is provided at a nipple portion at a supply path end downstream of a branch point to the pressure regulator. 3. The fuel supply device according to claim 1, wherein the check valve is provided between the fuel filter and a branch point to the pressure regulator. 4. A fuel filter housing comprising an upper housing made of a molded product of a polymer material for forming an oil-tight fuel filter by joining the main housing with a main housing enclosing the filter element, wherein the main housing is a fuel pump holding portion. The fuel supply device according to any one of claims 1 to 3, wherein a pressure regulator is connected to and attached to a supply path provided in the upper housing.